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Robin Foa

Publications and source records attributed to Robin Foa.

At least 19 recordsLinked to original sources

Role of interferon-alpha administration after 2-deoxycoformycin in the treatment of hairy cell leukemia patients.

BACKGROUND AND OBJECTIVE: Hairy cell leukemia (HCL) is a rare chronic B-cell lymphoproliferative disorder which is treated effectively by interferon-alpha (IFN-alpha), deoxycoformycin (DCF) and 2-clorodeoxyadenosine (2-CdA). As a third of patients treated with DCF do not achieve a complete remission (CR) and many of them tend to relapse, we evaluated the potential role of IFN-alpha, randomly administered after DCF, in increasing the number of patients attaining CR and/or duration of CR. METHODS: From March 1997 to December 2000, 167 previously untreated HCL patients, from 37 Italian institutions, were enrolled in the study. A total of 138 males and 29 females, with a median age of 55 yr were included in the study. All patients received six courses of DCF 4 mg/m(2) i.v. every other week and then two additional courses once a month. Complete and partial responders were randomly assigned to receive or not receive IFN-alpha at a dose of 3 MU s.c. three times a week for 6 months. RESULTS: Of the 167 patients enrolled in the study, 145 (86.8%) obtained a CR or a partial remission (PR) and were therefore suitable for randomization. One hundred and thirty-five patients were successively randomized to receive IFN-alpha (63 cases; arm A) or not (72 cases; arm B). Progression of disease was observed in eight (arm A) and 12 (arm B) patients with a median time of 27.8 and 26.9 months, respectively. As far as the improvement in response was concerned, no significant difference in the two subgroups was observed. In fact, five patients in arm A and six patients in arm B showing a good PR at the end of DCF therapy, subsequently attained a late CR. CONCLUSIONS: From our data there does not appear to be any significant role for IFN-alpha in improving the proportion and the duration of CR in HCL patients previously treated with DCF.

Adult↗

Diversity and functional consequences of germline and somatic PTPN11 mutations in human disease.

Germline mutations in PTPN11, the gene encoding the protein tyrosine phosphatase SHP-2, cause Noonan syndrome (NS) and the clinically related LEOPARD syndrome (LS), whereas somatic mutations in the same gene contribute to leukemogenesis. On the basis of our previously gathered genetic and biochemical data, we proposed a model that splits NS- and leukemia-associated PTPN11 mutations into two major classes of activating lesions with differential perturbing effects on development and hematopoiesis. To test this model, we investigated further the diversity of germline and somatic PTPN11 mutations, delineated the association of those mutations with disease, characterized biochemically a panel of mutant SHP-2 proteins recurring in NS, LS, and leukemia, and performed molecular dynamics simulations to determine the structural effects of selected mutations. Our results document a strict correlation between the identity of the lesion and disease and demonstrate that NS-causative mutations have less potency for promoting SHP-2 gain of function than do leukemia-associated ones. Furthermore, we show that the recurrent LS-causing Y279C and T468M amino acid substitutions engender loss of SHP-2 catalytic activity, identifying a previously unrecognized behavior for this class of missense PTPN11 mutations.

Adult↗

Genomic analysis in lymphoid leukemias.

The introduction of microarray analysis represents a revolution in the scientific field, allowing to investigate thousand of genes in a single experiment. Important biological insights have been revealed by this technique in several tumors: in acute lymphoblastic leukemia (ALL), these studies have allowed to identify specific patterns associated with known molecular abnormalities, as well as with phenotypic characteristics and with different prognostic features. In chronic lymphocytic leukemia (CLL), this approach has helped to dissect that this disease is a single entity with distinct variants that are characterized by a diverse IgVH mutational status, that can be discriminated by a small set of genes, has allowed to define a similarity between this disease and memory B cells and has also led to hypothesize that CLL cells from IgVH unmutated patients may be continuously stimulated in vivo, thus showing a gene profile that is reminiscent of the B cell receptor. In multiple myeloma (MM), gene expression profiles has provided insights into the disease and has offered the opportunity of stratifying patients according to the degree of aggressiveness of the disease. Current efforts are directed to the identification of patterns that may distinguish patients with a different outcome, thus providing useful prognostic information and to design experiments that may allow the identification of new therapeutic targets.

Gene Expression Profiling↗

Treatment of 72 newly diagnosed Waldenstrom macroglobulinemia cases with oral melphalan, cyclophosphamide, and prednisone: results and cost analysis.

BACKGROUND: Current treatment regimens for Waldenstrom macroglobulinemia (WM) are based on the use of oral alkylating agents. Recently, however, other more costly agents have been proposed for the treatment of WM. In the current study, the authors report on results obtained using oral melphalan, cyclophosphamide, and prednisone (MCP) to treat 72 patients with WM, and they compare these results (and the associated costs) with those observed using more aggressive protocols. METHODS: Between July 1973 and April 2002, the authors documented overexpression of the immunoglobulin M paraprotein in 317 consecutive patients. Of these, 100 had newly diagnosed WM, and the 72 who were symptomatic were treated using the MCP protocol. Response rate, overall survival (OS), response duration, freedom from progression (FFP), event-free survival (EFS) duration, toxicity, and cost per course in Euro and U.S. dollars were evaluated for patients receiving this regimen. RESULTS: Seventy-one of 72 patients (99%) were evaluable. Of these patients, 55 (77%) achieved a response; 7 others (10%) experienced disease stabilization, and the remaining 9 (13%) experienced disease progression. After a median follow-up of 72 months (range, 3-195 months), the median durations of EFS, FFP, response, and OS were 47, 55, 64, and 66 months, respectively. No World Health Organization Grade III or IV toxicities were observed, and side effects were limited to transient nausea, emesis, and mild neutropenia. The cost per course of the MCP regimen was $16, similar to that of standard protocols involving chlorambucil and much less than that of more aggressive protocols (price range, $91-11091) proposed for the treatment of WM. CONCLUSIONS: Like chlorambucil-based protocols, the MCP regimen is a cost-effective and safe option for the treatment of patients with WM. Furthermore, the results obtained do not appear to be inferior to those yielded by more expensive, aggressive, and toxic intravenous protocols.

Administration, Oral↗

A gender-based score system predicts the clinical outcome of patients with early B-cell chronic lymphocytic leukemia.

To facilitate the development of a prognostic model for early B-cell chronic lymphocytic leukemia (CLL), the Gruppo Italiano Malattie EMatologiche Maligne dell'Adulto (GIMEMA) proposes its multi-institutional effort as a working model. In total, 1138 newly diagnosed Binet stage A patients managed over the last 10 years outside the setting of clinical trials according to a "wait and see" policy form the basis of the present study aimed at investigating prognostic variables affecting disease progression, a surrogate endpoint for overall survival. A 3-stage risk system, simply obtained by summing the variables that proved significant in the multivariate analysis (i.e. short lymphocyte doubling time, advanced Rai substage, high peripheral blood lymphocytosis), is proposed. Clear-cut differences in the 10 year progression-free survival (PFS) were observed among patients scoring 0 (low risk), 1 (intermediate risk), 2-3 (high risk): 67.8, 41.0 and 24.8%, respectively (P<0.0001). The results of the Medical Research Council (MRC) suggesting a better clinical outcome for females prompted us to verify such a gender-related difference within our prognostic categories. Because changes in PFS only reflected gender for patients scoring 0 (P=0.04), the following prognostic subgroups are proposed: (1) females scoring 0; (2) males scoring 0; (3) patients scoring 1-3 whatever gender (10 year PFS: 76.2, 61.4 and 37.8%; P<0.00001). Our long-term database provides an adequate patient sample to generate a generalized risk stratification model based on clinical data. The indolent clinical outcome of women with early CLL is also supported by the higher frequency of the immunoglobulin heavy-chain variable (IgVH) mutational status and lower proportion of 17p and 11q deletions found in such a patient subset in the MRC CLL4 trial.

Adult↗

FLT3 inhibition in t(4;11)+ adult acute lymphoid leukaemia.

The present study was designed to investigate, in t(4;11)+ adult lymphoid leukaemia (ALL) blast cells, the pathogenetic role of the FLT3 protein, its level of mRNA and protein expression, the degree of constitutive phosphorylation, the possible presence of mutations of the sequence, the capacity of signal transduction and the potential therapeutic role of specific inhibitors. We evaluated nine adult ALL patients carrying this translocation. The increased FLT3 mRNA levels, determined by oligonucleotide microarray analysis, was in agreement with the increased protein expression evaluated by Western blot. The protein was constitutively phosphorylated in all cases analysed. Polymerase chain reaction detected no internal tandem duplication or point mutations. The signal transduction apparatus, after stimulation with the specific ligand, was preserved. We then investigated the effect of specific FLT3 inhibition on signal transduction and survival. The PKC412 inhibitor specifically inhibited ligand-induced phosphorylation; the same inhibitor reduced the survival of leukaemic cells when compared with untreated cells. These data indicate that the FLT3 protein might play a role in this subgroup of ALL with a particularly poor prognosis. Specific inhibition of the kinase receptor must be hypothesised as an innovative therapeutic tool for t(4;11)+ ALL patients.

Adult↗

Bayesian error-in-variable survival model for the analysis of GeneChip arrays.

DNA microarrays in conjunction with statistical models may help gain a deeper understanding of the molecular basis for specific diseases. An intense area of research is concerned with the identification of genes related to particular phenotypes. The technology, however, is subject to various sources of error that may lead to expression readings that are substantially different from the true transcript levels. Few methods for microarray data analysis have accounted for measurement error in a substantial way and that is the purpose of this investigation. We describe a Bayesian error-in-variable model for the analysis of microarray data from a clinical study of patients with acute lymphoblastic leukemia. We focus in particular on the problem of identifying genes whose expression patterns are associated with duration of remission. This is a question of great practical interest since relapse is a major concern in the treatment of this disease. We explore the effects of ignoring the uncertainty in the expression estimates on the selection and ranking of genes.

Bayes Theorem↗

Multiple distinct sets of stereotyped antigen receptors indicate a role for antigen in promoting chronic lymphocytic leukemia.

Previous studies suggest that the diversity of the expressed variable (V) region repertoire of the immunoglobulin (Ig)H chain of B-CLL cells is restricted. Although limited examples of marked constraint in the primary structure of the H and L chain V regions exist, the possibility that this level of restriction is a general principle in this disease has not been accepted. This report describes five sets of patients, mostly with unmutated or minimally mutated IgV genes, with strikingly similar B cell antigen receptors (BCRs) arising from the use of common H and L chain V region gene segments that share CDR3 structural features such as length, amino acid composition, and unique amino acid residues at recombination junctions. Thus, a much more striking degree of structural restriction of the entire BCR and a much higher frequency of receptor sharing exists among patients than appreciated previously. The data imply that either a significant fraction of B-CLL cells was selected by a limited set of antigenic epitopes at some point in their development and/or that they derive from a distinct B cell subpopulation with limited Ig V region diversity. These shared, stereotyped Ig molecules may be valuable probes for antigen identification and important targets for cross-reactive idiotypic therapy.

Amino Acid Sequence↗

Simple diagnostic assay for hairy cell leukaemia by immunocytochemical detection of annexin A1 (ANXA1).

A marker capable of distinguishing with certainty between hairy cell leukaemia and other B-cell malignant disease would be of great diagnostic value. Through gene expression profiling, annexin A1 (ANXA1) has been identified as a gene that is upregulated in hairy cell leukaemia. We did immunostaining of 500 B-cell tumours with a specific anti-ANXA1 monoclonal antibody and showed that ANXA1 protein expression is specific to hairy cell leukaemia. Immunocytochemical detection of ANXA1 represents a simple, inexpensive, highly sensitive and specific (100%) assay for diagnosis of hairy cell leukaemia. This assay will be especially useful in distinguishing hairy cell leukaemia from splenic lymphoma with villous lymphocytes and variant hairy cell leukaemia, both of which usually respond poorly to treatments that are effective in hairy cell leukaemia.

Annexin A1↗

Gene expression profiling of hairy cell leukemia reveals a phenotype related to memory B cells with altered expression of chemokine and adhesion receptors.

Hairy cell leukemia (HCL) is a chronic B cell malignancy characterized by the diffuse infiltration of bone marrow and spleen by cells displaying a typical "hairy" morphology. However, the nature of the HCL phenotype and its relationship to normal B cells and to other lymphoma subtypes remains unclear. Using gene expression profiling, we show here that HCL displays a homogeneous pattern of gene expression, which is clearly distinct from that of other B cell non-Hodgkin lymphomas. Comparison with the gene expression profiles of purified normal B cell subpopulations, including germinal center (GC), pre-GC (naive), and post-GC (memory) B cells, shows that HCL cells are more related to memory cells, suggesting a derivation from this B cell population. Notably, when compared with memory cells, HCL cells displayed a remarkable conservation in proliferation, apoptosis, and DNA metabolism programs, whereas they appeared significantly altered in the expression of genes controlling cell adhesion and response to chemokines. Finally, these analyses have identified several genes that are specifically expressed in HCL and whose expression was confirmed at the protein level by immunocytochemical analysis of primary HCL cases. These results have biological implications relevant to the pathogenesis of this malignancy as well as clinical implications for its diagnosis and therapy.

B-Lymphocytes↗

Immunomodulating effect of antimicrobial agents on cytokine production by human polymorphonuclear neutrophils.

It has been previously demonstrated that some antimicrobial agents enhance activities of human polymorphonuclear neutrophils (PMNs). The effect on the release of cytokines in an inflammatory context from PMNs by these antibiotics was evaluated. We studied the effect of the release of some cytokines by human PMNs RT-PCR analysis on a clinical strain of Klebsiella pneumoniae by comparing the effect with that observed in the presence of co-amoxiclav, sanfetrinem, clarithromycin, prulifloxacin and tobramycin. All the drugs tested were capable of modulating PMN synthesis in vitro of pro-inflammatory cytokines IL-8, IL-1beta, TNF-alpha and IL-6, but not that of anti-inflammatory cytokine IL-10. The degree of their stimulatory or inhibitory potency varied with the cytokine examined.

Anti-Bacterial Agents↗

Resistance to CD95-mediated apoptosis of CD40-activated chronic lymphocytic leukemia B cells is not related to lack of DISC molecules expression.

In B-cell chronic lymphocytic leukemia (CLL), accumulation of neoplastic B cells may be the result of dysregulated apoptosis. One of the major molecules triggering apoptosis, CD95 (FAS), is not expressed on CLL B cells at resting conditions. However, CD40 triggering of CLL B cells upregulates receptors belonging to the tumor necrosis factor (TNF) superfamily, like CD95. In the present study, we analyzed in B cells from 20 CLL patients the effect of CD40/CD40L interaction on: (i) CD95 modulation; (ii) CD95-mediated apoptosis and (iii) mRNA and protein expression of the death-inducing signaling complex (DISC) molecules.CD40 activation of CLL B cells was carried out by coculture with CD40L-transfected cells and cytofluorimetric analyses were performed to study CD95 modulation and apoptosis induction by an anti-CD95 moAb. Despite strong CD95 upregulation on the membrane of all the cases studied, only a minority of cases analyzed (3/20) proved weakly responsive to CD95-mediated apoptosis. Multiplex RT-PCR was used to analyze FLICE, FAS, FADD and TRADD mRNAs before and after CD40 triggering. In agreement with the cytofluorimetric data, FAS mRNA appeared significantly increased after CD40 triggering; the other molecules involved in DISC formation and in CD95-mediated apoptosis were also expressed without relevant differences between resting and activated conditions. Western blot analyses further confirmed FLICE and FADD protein expression by resting and activated CLL cells. Our findings demonstrate that, following CD40 triggering, CLL B cells are resistant to CD95-mediated apoptosis despite a strong CD95 upregulation on the membrane and a normal mRNA or protein expression of the DISC components.

Adaptor Proteins, Signal Transducing↗

Phenotypic and functional characterization of monocyte-derived dendritic cells in chronic lymphocytic leukaemia patients: influence of neoplastic CD19 cells in vivo and in vitro.

Dendritic cells (DCs) are the most potent antigen-presenting cells and are therefore an attractive option as antigen carriers in vaccination protocols. Chronic lymphocytic leukaemia (CLL) represents a potential good target for these approaches. The present study was designed to investigate the feasibility of generating in vitro fully functional DCs from peripheral blood (PB) monocytes of CLL patients at different phases of the disease. Although functional DCs could be obtained from CLL samples, in patients with active disease the expression of some co-stimulatory molecules appeared to be reduced. In contrast, DCs from CLL patients in remission showed no difference from those of normal controls. Moreover, patients with active disease produced DCs with reduced allostimulatory ability when compared with normal ones, whereas the functional capacities appeared to be restored in CLL DCs from remission patients. To more precisely assess the possible inhibitory effect of CLL cells on DC development, the influence of autologous leukaemic CD19(+) cells on the generation of monocyte-derived CLL DCs in vitro was investigated. The addition of CLL neoplastic cells markedly affected monocyte-derived DC maturation. In conclusion, monocytes from CLL patients with active disease give rise to DCs, which show phenotypic and functional defects that are not observed in remission CLL patients. These results need to be taken into account in the design of DC-based immunotherapeutic approaches in CLL.

Adult↗

Gene expression profile of adult T-cell acute lymphocytic leukemia identifies distinct subsets of patients with different response to therapy and survival.

Gene expression profiles were examined in 33 adult patients with T-cell acute lymphocytic leukemia (T-ALL). Nonspecific filtering criteria identified 313 genes differentially expressed in the leukemic cells. Hierarchical clustering of samples identified 2 groups that reflected the degree of T-cell differentiation but was not associated with clinical outcome. Comparison between refractory patients and those who responded to induction chemotherapy identified a single gene, interleukin 8 (IL-8), that was highly expressed in refractory T-ALL cells and a set of 30 genes that was highly expressed in leukemic cells from patients who achieved complete remission. We next identified 19 genes that were differentially expressed in T-ALL cells from patients who either had a relapse or remained in continuous complete remission. A model based on the expression of 3 of these genes was predictive of duration of remission. The 3-gene model was validated on a further set of T-ALL samples from 18 additional patients treated on the same clinical protocol. This study demonstrates that gene expression profiling can identify a limited number of genes that are predictive of response to induction therapy and remission duration in adult patients with T-ALL.

Adult↗

Clinico-biologic features and treatment outcome of adult pro-B-ALL patients enrolled in the GIMEMA 0496 study: absence of the ALL1/AF4 and of the BCR/ABL fusion genes correlates with a significantly better clinical outcome.

To elucidate the biologic and clinical heterogeneity of adult pro-B acute lymphoblastic leukemia (ALL) (ie, terminal deoxynucletidyl-transferase-positive[TdT+], CD19+, CD10-, surface immunoglobulin-negative [SIg-]), we evaluated 66 patients enrolled in the Italian multicentric Gruppo Italiano Malattie Ematologiche dell'Adulto (GIMEMA) 0496 study between October 1996 and December 1999. The ALL1/AF4 fusion transcript, originating from the t(4;11) translocation, was detected in 24 patients (36.4%), and the BCR/ABL chimeric product was found in 6 patients (9%), while the remaining 36 cases (54.6%) were ALL1/AF4-BCR/ABL-negative. A white blood cell (WBC) count higher than 50 x 109/L was found in 13 of 24, 2 of 6, and 6 of 36 of the ALL1/AF4-positive, BCR/ABL-positive, and ALL1/AF4-BCR/AB-negative patients, respectively (P =.007). None of the 24 ALL1/AF4-positive patients coexpressed the CD13 and/or CD33 myeloid antigens. By contrast, CD13 and CD33 molecules were detected, respectively, in 3 of 6 and in 14 of 33 cases of the BCR/ABL-positive patient group, and in 2 of 6 and 9 of 35 cases of the ALL1/AF4-BCR/ABL-negative patient group. These differences still remained statistically significant even if the BCR/ABL-positive patients were excluded from the analysis. A complete remission (CR) was achieved in 52 (83.4%) of the 62 patients with ALL evaluable for response to treatment. CR rates were similar in the 3 genotypic groups. By contrast, comparing patients with or without the ALL1/AF4 gene the probability of remaining in continuous complete remission (CCR) at 3.5 years was 16% and 49.8%, respectively (P =.005). Our data demonstrate that in adult pro-B-ALL a distinction should be made between pro-B-ALL cases with and without the ALL1/AF4 or the BCR/ABL chimeric genes, since the absence of both of these fusion genes correlates with a significantly better clinical outcome after intensive polychemotherapy treatment without hematopoietic stem cell transplantation.

Adolescent↗

Defective expression of the T-cell receptor-CD3 zeta chain in T-cell acute lymphoblastic leukaemia.

This study analysed the T-cell receptor (TCR)-CD3 zeta complex and the signal transduction apparatus of T-acute lymphoblastic leukaemia (T-ALL) blasts, and investigated the function of the ubiquitin-proteasome system. In all nine T-ALL samples studied, the leukaemic cells showed a marked reduction in the expression of the zeta chain, while a variety of tyrosine kinases (p56lck, ZAP70 and SYK) were normally present. There was no expression of the FcepsilonRIgamma chain. To confirm that this aberration was specific to immature T-ALL blasts, we investigated two patients with lymphoproliferative disorders of granular lymphocytes (LDGL), characterized by the expansion of mature T lymphocytes and found normal zeta chain expression. The reduction of the zeta chain protein was not reversible after 72 h stimulation with the anti-CD3 monoclonal antibody and interleukin 2, either alone or in combination. Northern blot analysis indicated that the reduced protein expression did not correspond to a defect at the mRNA level, nor were mutations in the coding region of the zeta chain found. We, therefore, hypothesized that the observed reduction of protein expression in T-ALL blasts could be secondary to an increased degradation at the proteasome level. Following selective inhibition of the proteasome, a marked increase of the zeta chain expression was observed. Moreover, an increase in the surface expression of CD3 was also documented. Taken together, these results indicate that the expression of the zeta subunit of the TCR-CD3 complex is consistently reduced in T-ALL blasts and that degradation of the protein is mediated by the proteasome system.

Adult↗

E2A-PBX1 fusion in adult acute lymphoblastic leukaemia: biological and clinical features.

Molecular and cytogenetic studies performed in 305 adult acute lymphoblastic leukaemia (ALL) patients enrolled in the gimema (Gruppo Italiano Malattie EMatologiche dell'Adulto) multicentric protocols identified an E2A-PBX1 fusion and/or t(1;19) in 10 patients (3.3%). All had common ALL, were mostly CyIg+ and were CD34/CD13/CD33-. Nine patients achieved a complete remission (CR); five patients showed a haematological relapse after 7 months (median). Four patients are alive in first CR with a median follow-up of 29 months; three patients are molecularly negative. This abnormality is frequently associated with early treatment failure. E2A-PBX1+ adult ALL should be considered for intensified treatment strategies and monitoring of minimal residual disease.

Adolescent↗